LTC3527-1_15 Datasheet, PDF (3/22 Pages) Linear Technology – Dual 800mA/400mA, 1.2MHz/2.2MHz Synchronous Step-Up DC/DC Converters

LTC3527/LTC3527-1
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, –40°C to 85°C. V_IN = V_IN1 = V_IN2 = 1.2V, V_OUT1 = V_OUT2 = 3.3V, T_A = 25°C, unless otherwise noted.
PARAMETER
CONDITIONS
PMOS Switch Leakage Current (LTC3527)
V_SW1,2 = 5V, V_OUT1,2 = 0V, SHDN1,2 = 0V
NMOS and PMOS Combined Switch Leakage Current V_SW1,2 = 5V, V_OUT1,2 = 0V, SHDN1,2 = 0V (Note 6)
(LTC3527-1)
NMOS Switch On-Resistance, SW1
MIN TYP MAX UNITS
0.1
10
μA
0.2
20
μA
0.30
Ω
NMOS Switch On-Resistance, SW2
0.50
Ω
PMOS Switch On-Resistance, SW1
0.40
Ω
PMOS Switch On-Resistance, SW2
0.60
Ω
NMOS Current Limit, SW1
l 800
mA
NMOS Current Limit, SW2
l 400
mA
Current Limit Delay to Output Time
(Note 4)
60
ns
Maximum Duty Cycle
Minimum Duty Cycle
Switching Frequency
Switching Frequency
SHDN1,2 Input High Voltage
SHDN1,2 Input Low Voltage
SHDN1,2 Input Current
PGOOD1, PGOOD2 Threshold
V_FB1,2 = 1V
V_FB1,2 = 1.3V
V_FSEL = 0V
V_FSEL = 3.3V
V_SHDN1,2 = 3.3V
Referenced to the Feedback Voltage
l 85
90
%
l
0
%
l 0.9
1.2
1.5
MHz
l 1.8
2.2
2.8
MHz
0.88
V
0.35
V
1
2
μA
–6
–9
–14
%
PGOOD1, PGOOD2 Low Voltage
PGOOD1, PGOOD2 Leakage Current
MODE Input High Voltage
I_PGOOD1,2 = 1mA
V_PGOOD1,2 = 5.25V
0.1
0.2
V
0.01
1
μA
1
V
MODE Input Low Voltage
0.35
V
MODE Input Current
FSEL Input High Voltage
V_MODE = 3.3V
1
2
μA
0.88
V
FSEL Input Low Voltage
0.35
V
FSEL Input Current
Soft-Start Time
V_FSEL = 3.3V
1
2
μA
0.5
ms
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3527E/LTC3527E-1 are guaranteed to meet performance
specifications from 0°C to 85°C. Specifications over the –40°C to 85°C
operating temperature range are assured by design, characterization and
correlation with statistical process controls.
Note 3: Current is measured into the V_OUT pin since the supply current is
bootstrapped to the output. The current will reflect to the input supply by:
(V_OUT/V_IN) • (1/Efficiency). All switches are off.
Note 4: Specification is guaranteed by design and not 100% tested in
production.
Note 5: The LTC3527/LTC3527-1 includes an overtemperature shutdown
that is intended to protect the device during momentary overload
conditions. Junction temperature will exceed 125°C when the over-
temperature shutdown is active. Continuous operation above the specified
maximum junction temperature may impair device reliability.
Note 6: The NMOS and PMOS switch leakage currents are tested in parallel
for the LTC3527-1 because V_OUT1,2 are actively pulled to ground when
SHDN1,2 = 0V
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